Diamondback 16" Black Nitride 4150 CMV Steel 300 Blackout Pistol-Length OEM Replacement Barrel

The Diamondback 16" Black Nitride 300 Blackout pistol-length barrel is a heavy-profile replacement barrel built for shooters who want reliability and durability in a shorter, handy configuration. Machined from 4150 Chrome Moly steel and finished with black nitride coating, this OEM-pattern barrel integrates into existing 300 Blackout AR builds without fuss—whether you're running subsonic loads for suppressed shooting or pushing supersonic velocity. The pistol-length gas system keeps the receiver action smooth and controllable in shorter barreled platforms where mid-length or rifle-length gas would cause feeding or reliability issues.

Precision starts at the bore. Diamondback's button-rifled 5-groove profile uses a 1:8 twist rate, a standard choice for stabilizing both lightweight and heavier projectiles in 300 Blackout across the speed spectrum. The barrel ships with M4 feed ramps cut to spec, ensuring compatibility with standard AR magazines and bolts, and threads 5/8x24 for direct fit with common 300 Blackout suppressors and muzzle devices. An 11° target crown protects the rifling and supports accuracy by maintaining even bullet release at the muzzle.

Black nitride coating resists corrosion and requires only basic field cleaning—no daily babying. The heavy contour absorbs heat and vibration, helping maintain consistency shot to shot. This is a straightforward drop-in replacement for shooters who want a quality barrel without custom gunsmithing or headspace guesswork.

Key Features

• 4150 Chrome Moly steel with black nitride corrosion-resistant finish
• Pistol-length gas system for short-barreled 300 Blackout builds
• Heavy profile contour for improved heat management and shot-to-shot consistency
• Button-rifled 5-groove bore with 1:8 twist for subsonic and supersonic loads
• M4 feed ramps for reliable function with standard AR components
• 5/8x24 thread pitch for common suppressors and muzzle devices
• 11° target crown for precision and bore protection
• OEM-pattern design for direct compatibility with existing AR receivers

Specifications

Frequently Asked Questions

Will this barrel work in my 300 Blackout AR pistol or SBR?

Yes. The 16" length with pistol-length gas system is designed for shorter AR platforms. Verify your receiver is chambered in 300 Blackout and confirm headspace before assembly—though this barrel follows OEM specifications, always confirm compatibility with your specific upper receiver or have a gunsmith verify fit.

Is this barrel compatible with a suppressor?

The barrel is threaded 5/8x24, the standard suppressor thread pitch for 300 Blackout. It will accept any suppressor or muzzle device in that pattern. Always verify your suppressor is rated for the specific cartridge and pressure you're running.

Can I use both subsonic and supersonic 300 Blackout ammo in this barrel?

The 1:8 twist rate is a common all-around twist for 300 Blackout and will stabilize a wide range of subsonic and supersonic loads. Actual performance depends on bullet weight, velocity, and barrel length—lighter bullets at high velocity or heavier bullets at subsonic speeds may require load-specific testing for your needs.

What gas tube length do I need if I'm replacing a barrel?

This is a pistol-length gas barrel, so you'll need a pistol-length gas tube in your upper receiver. If you're swapping from a mid-length or rifle-length barrel, you'll also need to swap the gas tube to match—using the wrong tube length can cause feeding or cycling issues.